Tindfjallajökull is one of the oldest late-Quaternary volcanoes of the eastern volcanic zone of Iceland, and has produced rocks of basaltic-to-rhyolitic composition. The NW rim of the 5-km-wide caldera is topped by an icecap. About a dozen small eruptions took place during the late Pleistocene or early Holocene, mostly from vents north and west of the caldera. Although previously thought to be the source of the nearby Thórsmörk Ignimbrite deposits, Moles et al. (2019) showed that they originated from Torfajökull (about 30 km NE).